Whoa big difference!
Thread Starter
Instructor
Joined: Jul 2002
Posts: 132
Likes: 0
From: Little Rock AR
Whoa big difference!
Just changed my old splitfire plugs to bosch platinums and the wires to MSD superconductorsin my 75 L48. The engine idles better, has faster throttle response, and starts easier. All for about $80.00! The wires on the passenger side were a pain though. Would have had to remove the starter to get the shield off to get them off.
Melting Slicks
Joined: Dec 2000
Posts: 3,407
Likes: 2
From: Carmichael CA
Re: Whoa big difference! (vettinator)
Yeah, but the increase in performance also indicates that you weren't getting good ignition prior to the change. That means perhaps some valves may not be sealing well. I recommend doing a compression check in case one of the cylinders isn't like the others. I had a Pinto that I managed to get running well with some Bosch Platinums, then tore the engine apart about five months later and discoverd one exhaust valve with 1/4 of the valve missing, and another exhaust valve with a crack running from lip to stem with only about 1/16 of it missing. It ran great, but was overheating bad.
Thread Starter
Instructor
Joined: Jul 2002
Posts: 132
Likes: 0
From: Little Rock AR
Re: Whoa big difference! (Rockn-Roll)
Good Idea. I had crappy wires on there with splitfire plugs. They only had 7000 miles on them, but that was over 4 summers of driving. The old plugs all looked the same, white and brittle.
Abby Normal
Joined: Dec 2001
Posts: 53,440
Likes: 92
From: Press "2" for English
Re: Whoa big difference! (Stevo)
stevo, basically, you can do a leak down test at the same time you do a compression test. the gauge is slightly different though. on a leak-down test what your looking for is how many PSI each cylinder drops after it has been stopped. i haven't actually done one so i'm just giving you information which may or may not be totally correct. i do know the idea, it's just the actual proceedure i'm not terribly sure of. what you need is a gauge that doesn't have a check valve to hold the pressure in the line. you need a manual relief valve but the idea is to get the compression in the cylinder up and see how much you loose and how rapidly. this all requires that you can stop the engine at TDC with the valves closed, of course. if the pressure in the cylinder bleeds down rapidly, then that is an indication you have internal 'issues' with that cylinder. maybe someone with practical experience can elaborate on how this is done. if nobody answers here, i suggest you go to the engine mod section and ask there. i'm listening too. :cheers:
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